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1.
Article in English | MEDLINE | ID: mdl-38970631

ABSTRACT

Ammonia is a gas that produces zero carbon emissions when used in energy storage systems. Hence, there is increasing interest for the application of ammonia as fuel in various energy storage devices, specifically solid oxide fuel cells (SOFCs), as it has the potential to be efficient and environmentally friendly. In addition, compared to other fuel cells, SOFCs fed with ammonia offer various benefits such as such as sustainability and safety. This review compares and contrasts the opportunities and challenges of ammonia fuel cell technologies and helps to analyze their working principles. The main goal of this review is to investigate the viability of an "all-protonic" fuel cell using ammonia fuel while also highlighting the key challenges and limitations of implementing such technology.

2.
Environ Sci Pollut Res Int ; 31(2): 1907-1925, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38091225

ABSTRACT

The use of humidification-dehumidification water desalination technology has been shown to be a practical means of meeting the demand for freshwater. The aim of this review is to investigate the impact of salinity on HDH techniques that have various benefits in terms of both economics and the environment, including the capacity to operate at low temperatures, utilize sustainable energy sources, the need for low maintenance, and straightforward construction requirements. Also, in this review, it is observed that the HDH system's components are strong and capable of treating severely salinized water. It can treat water in an appropriate way than other desalination technologies. This technology has recently been commercialized to treat highly salinized generated water. However, more research is needed to determine how salinity affects HDH productivity. According to several research investigations, while the specific thermal energy consumption increased considerably and the productivity of water per unit of time decreased significantly as the salt mass percentage grew, the purity of clean water did not suffer. The rejected brine must be reduced by increasing the total water recovery ratio in the HDH system. Through this review, it was found that brine control is becoming increasingly important in the water processing industry. ZLD systems, which aim to recover both freshwater and solid salts, can be a viable replacement for disposal methods. Finally, through this reviewer, it was concluded that HDH desalination systems may operate with extremely saline water while increasing salinity has a significant influence on system performance.


Subject(s)
Salinity , Water Purification , Water Purification/methods , Salts , Sodium Chloride
3.
Environ Sci Pollut Res Int ; 30(24): 66135-66156, 2023 May.
Article in English | MEDLINE | ID: mdl-37097568

ABSTRACT

Solar stills are used in distant and arid areas to convert brackish or salty water into potable water fit for human use in a simple, affordable, and effective manner. Even when PCM materials are used, typical solar systems still have minimal production per day. In this study, experimental tests were carried out in order to increase the performance of a single-slope solar still combined with PCM material (paraffin wax) and a solar-powered electric heater. Two identical single-slope solar stills were designed, fabricated, and tested under the same climatic conditions during the summer and spring seasons of 2021 in Al-Arish, Egypt. The first is a conventional solar still (CVSS), and the other is also a conventional still but with PCM and an electric heater (CVSSWPCM). Several parameters were measured during the experiments, including sun intensity, meteorological aspects, cumulative freshwater production, average glass, and water temperatures and PCM temperature. The improved solar still was evaluated at different operating temperatures and was compared to the conventional traditional one. There were four cases studied: one case without a heater (paraffin wax only) and three other cases with a heater operating at 58 °C, 60 °C, and 65 °C, respectively. The experimental results revealed that activating the heater inside the paraffin wax increased daily production (i) in the spring by 2.38, 2.66, and 3.1 times and (ii) and in the summer by 2.2, 2.39, and 2.67 times at the three above-mentioned temperatures respectively (when compared to the traditional still). In addition, the maximum rate of daily freshwater production was achieved at paraffin wax temperature of 65 °C in both spring and summer (Case 5). Finally, the economic evaluation of the modified solar still was carried out according to cost per litre. The modified solar still with a heater operating at 65 °C has a higher exergoeconomic value than the traditional one. The maximum CO2 mitigation in cases 1 and 5 was approximately 28 tons and 160 tons, respectively.


Subject(s)
Solar Energy , Humans , Paraffin , Cost-Benefit Analysis , Egypt , Water
4.
Afr Health Sci ; 22(1): 602-610, 2022 Mar.
Article in English | MEDLINE | ID: mdl-36032461

ABSTRACT

Background/Aim: Ulcerative Colitis (UC) is an inflammatory bowel disease which is common in many areas of the world including Egypt. A lot of controversy regarding the pathogenesis of UC exist. The current study is an attempt to detect some pathogenic bacteria in UC patients. Materials and methods: Endoscopic colonic biopsies obtained from 40 patients with ulcerative colitis and 20 controls were analyzed by means of real-time PCR technique for the presence of Clostridium difficile, Helicobacter Pylori (H. pylori) and pathogenic Escherichia Coli (E. coli) which are positive for KPC and/or OXA-48. Results: All patients and control samples were negative for Clostridium difficile. Three of the 40 patient samples (7.5%) and none of the 20 controls were positive for H. pylori with no significant difference between the two groups. KPC-positive E. coli were detected in 11 of the 40 patients (27.5%) and in none of the controls with a significant difference between the two groups (P=0.01). All patients and control samples were negative for OXA-48 positive E. coli. Conclusion: Although this study does not support the claim that Clostridium difficile and/or H. pylori have a role in UC, it greatly suggests that pathogenic E. coli may be involved in one way or another in the course of UC.


Subject(s)
Clostridioides difficile , Colitis, Ulcerative , Escherichia coli Infections , Helicobacter pylori , Biopsy , Escherichia coli , Humans
5.
Environ Sci Pollut Res Int ; 29(43): 65787-65805, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35499732

ABSTRACT

This study focused on experimentally increasing the productivity of freshwater from solar stills. The performance of a single solar still system could be augmented with the combination of an electric heater, vibration motion, and thermoelectric cooling. The study investigated the effects of combining two of these components and finally combining all of them on freshwater productivity. The electric heater and vibration motion are used to enrich the evaporation rate, while thermoelectric coolers are used to enhance the condensation rate, leading to high freshwater productivity. The proposal, construction, and testing of two identical solar stills were performed under the local climate conditions of the city of Alexandria in northwestern Egypt during the summer and winter times. The two solar stills had a 1-m2 base area. An electric heater of 450 W was placed inside the modified solar still. The modified solar still was fixed on four coiled springs. A 1-hp power DC motor, an inverter, a control unit, and two 330-W photovoltaic solar panels were attached to the modified solar still. Eccentric masses were mounted on the rotating disk attached to the DC motor to generate the vibration. Under the same climate conditions, the daily output of freshwater was measured experimentally for the modified case and the conventional solar. The daily rates of freshwater productivity in summer were investigated for four cases and the conventional one. Results showed that the peak daily freshwater productivity achieved with the solar heater, thermoelectric coolers, and vibration motion was 12.82 kg/day, with a maximum estimated cost of 0.01786 $/L/m2.The exergoeconomic of the modified solar still with heater, vibration, and thermoelectric cooler was greater than that of conventional ones. The highest CO2 mitigation of the case (5) and that of the conventional solar desalination were about 160 tons and 28 tons, respectively.


Subject(s)
Solar Energy , Vibration , Carbon Dioxide , Fresh Water , Phase Transition , Sunlight
6.
Acta Oncol ; 61(5): 583-590, 2022 May.
Article in English | MEDLINE | ID: mdl-35392758

ABSTRACT

BACKGROUND: Identifying pretreatment blood markers that distinguish prognostic groups of patients with advanced pancreatic ductal adenocarcinoma (PDAC) under first-line FOLFIRINOX chemotherapy has the potential to improve management of this condition. Aim of this study was to determine the prognostic utility of a range of pretreatment, inflammation-related, blood cell markers in this group of patients. MATERIAL AND METHODS: Data from a training cohort were analyzed to identify potential pretreatment blood markers correlating to survival outcomes. The most informative markers were further analyzed in a validation cohort comprised patients from a geographically separate cancer center undergoing the same treatment. RESULTS: A total of 138 consecutive patients receiving FOLFIRINOX chemotherapy between 2010 and 2019, constituted the training cohort. Neutrophil/lymphocyte (NLR), monocyte/lymphocyte (MLR), and platelet/lymphocyte ratio (PLR) as well as the systemic inflammatory response index (SIRI) and CA19.9 showed prognostic significance in addition to tumor stage. A pretreatment SIRI score cutoff of 2.35 differentiated between a poor prognostic group with median overall survival (mOS) 5.1 months and a better prognostic group, mOS 12.5 months. SIRI ≤/> 2.35 was predictive of mOS in patients with locally advanced and metastatic PDAC. SIRI was confirmed as a prognostic marker in a validation cohort of 67 patients with mOS of 13.4 months and 6.3 months for those with SIRI ≤ 2.35 and >2.35, respectively. Additional analysis revealed baseline SIRI as being prognostic within additional subgroups of patients in both cohorts. CONCLUSIONS: This large, retrospective, analysis of real-world patients receiving first-line FOLFIRINOX chemotherapy for advanced PDAC has identified the pretreatment blood SIRI as a strong prognostic marker for survival. This will allow better counseling of patients with regards to the benefits of treatment, improved stratification within clinical trials, and potentially identify groups of patients for novel therapy trials as first-line treatment.


Subject(s)
Adenocarcinoma , Pancreatic Neoplasms , Adenocarcinoma/drug therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers , Fluorouracil , Humans , Inflammation/pathology , Irinotecan , Leucovorin , Oxaliplatin , Pancreatic Neoplasms/drug therapy , Prognosis , Retrospective Studies , Pancreatic Neoplasms
7.
East Mediterr Health J ; 24(11): 1103-1111, 2019 Jan 23.
Article in English | MEDLINE | ID: mdl-30701526

ABSTRACT

BACKGROUND: Although inborn errors of metabolism (IEM) are rare individually, collectively IEM cause substantial morbidity and mortality and the diagnosis is challenging. AIMS: To analyse epidemiological and clinical data, final diagnosis and clinical outcomes of patients with a suspected diagnosis of IEM (small molecule disorders type) admitted to a paediatric intensive care unit (PICU). METHODS: We collected and analysed medical records data of all patients admitted to the PICU at Alexandria University Children's Hospital, from January 2010 to December 2014, with a suspected or confirmed diagnosis of small molecule disorders, including clinical presentations, laboratory results and clinical outcomes. RESULTS: A total of 34 patients had a suspected or confirmed diagnosis of small molecule disorders at PICU admission. Diagnosis was confirmed in 22.7% of suspected cases at admission and in 25% of suspected cases during PICU stay. Consanguineous marriage was found in 50% of cases with confirmed small molecule disorders. CONCLUSIONS: A high index of suspicion is important for diagnosing and categorizing small molecule disorders in screening of high-risk individuals in low- and middle-income countries.


Subject(s)
Intensive Care Units, Pediatric/statistics & numerical data , Metabolism, Inborn Errors/epidemiology , Child , Child, Preschool , Consanguinity , Egypt/epidemiology , Female , Humans , Infant , Infant, Newborn , Male , Metabolism, Inborn Errors/diagnosis , Metabolism, Inborn Errors/etiology , Metabolism, Inborn Errors/mortality , Retrospective Studies , Risk Factors
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